KABUL, Afghanistan — Army Command Sgt. Maj. Marvin Hill is not a household name among Marines, but his career has skyrocketed parallel to that of his long-time friend, Sgt. Maj. Carlton Kent, who stepped down June 9 as sergeant major of the Marine Corps. “I went to high school with Sgt. Maj. Kent, he’s a homeboy and a very close friend,” Hill said June 3 in his office at NATO headquarters, where he is the senior enlisted leader for International Security Assistance Force and U.S. Forces Afghanistan. Translation: He is ISAF commander Army Gen. David Petraeus’ wingman, and has…